Bernard tiiayer



(No Model.)

B. THAYER DIE STOCK.

Patented Feb.- 7, 1893.

UNHED STATES PATENT Onnicn.

BERNARD TI'IAYER, OF BOSTON, MASSACHUSETTS, ASSIGNOR OF ONE-HALF TOCHARLES H. STUART, OF SAME PLACE.

DlE-STOC K.

SPECIFICATION forming part of Letters Patent No. 491,453, dated February7, 1893.

Application filed March 3, 1892. Serial No, 424,123. (No model.)

To all whom it 11mg concern:

Be itknown that I, BERNARD THAYER, of Boston, county of Suffolk, Stateof Massachusetts, have invented an Improvement in Die- 5 Stocks, ofwhich the following description, in connection with the accompanyingdrawings, is a specification, like letters on the drawings representinglike parts.

This invention relates to die-stocks, and

[O has for its object to improve the same in a manner calculated tofacilitate the change in adjustment required for work of various sizes.

Die-stocks as at present constructed are provided at one side with aguide or bushing which runs upon the pipe or rod upon which the threadis being out to serve as a guide for the die-stock as the latter isrotated. These guides or bushings must fit the rod or pipe beingthreaded in order to properly guide the die-stock as it is rotated sothat a true thread will be out, a change in bushing being necessarywhenever the die-stock is used upon a pipe or rod of a differentdiameter or size, thus requiring constantly a large stock of bushing ofvarious sizes to fit the many sizes of pipe or rod upon which threadshave to be out.

In accordance with this invention the diestock is provided with apermanent guide or support of a diameter to receive the smallest orlargest pipe or rod upon which the diestock is capable of being used,said support at its outer end carrying a series of adjustable jaws whichmay be moved toward and from the center of the guide by suitable meansto accommodate and fit any diameter of rod or pipe.

One part of this invention therefore consists 4c in a die-stock providedwith a long guide or support extended from its rear side, and a seriesof adjustable jaws carried by said guide at its outer end, and adjustingdevices therefor intermediate said jaws and die stock, substantially aswill be described.

Other features of this invention will be hereinafterdescribed, andpointed out in the claim at the end of this specification.

The drawings Figure 1, represents in side elevation the body portion ofa die-stock embodying this invention. Fig. 2, a face view of the same.Fig. 3, an enlarged section on the dotted line m:n, Fig. 2. Figs. 4 and5 details to be referred to.

Referring to the drawings, A represents a die-stock which may be ofusual or desired construction, it being herein represented as providedwith a recess to receive the die a, held in position by the hinged platea and clamping screw a In accordance with this invention, the diestock Aupon its rear side is provided with a preferably, tubular guide orsupport I) in line with the cutting portion of the die, said guide atits outer end carrying the fixed head 0 provided with a series ofguide-ways 0', herein shown as four in number, to receive theradially-adjustable jaws (1 preferably having their inner ends beveledas at (Z to permit the jaws to be moved closer together to accommodatethe smallest possible diameter of rod or pipe. The adjustable jaws d areprovided with pins or studs (Z which enter suitable cam grooves c in therotatable cam head c mounted loosely upon the guide I) and provided witha clamping screw e which preferably runs in a groove cut in the surfaceof the guide to thereby keep the cam head up to the fixed head 0', saidclamping screw when turned acting as a clamp to hold 5,

the cam head in adjusted position.

In operation the clamping screw 6 when loosened, permits the cam head 6to be rotated in one or the other direction so that it its cam grooves ewill act upon the pins (Z on the adjustable jaws cl to move the lattertoward or from the common center to accommodate pipes or rods of varyingsizes.

I claim- A die-stock having a long tubular guide or support 1) extendedfrom its rear side and annularly grooved at b an enlarged head fixed tothe extremity of the guide and having radial guide-ways upon its innerface, and adj ustable jaws movable therein, combined with an independentcam-head rotatable on said guide intermediate the die stock and jaws Intestimony whereof I have signed my and abutting against the latter,cam-surfaces name .to this specification in the presence of to act uponthe jaws and move them, and a two subscribing witnesses.

clamping screw carried by the cam-head and BERNARD THAYER. 5 enteringthe annular groove to serve as a re- Witnesses:

raining and clamping device for said cam- FREDERICK L. EMERY,

head, substantially as described. FRANOEs M. NOBLE.

